The application discloses a method of joining at least four heat transfer plates (2) to a plate package for a plate heat exchanger. Each heat transfer plate (2) comprises an outer edge portion (10) extending around the heat transfer plate in its edge area and an inner edge portion (11) extending around the heat transfer plate inside the outer edge portion (10). The heat transfer plates (2) are joined in pairs at a first contact plane to at least two plate pairs (16) along said inner edge portions (11). An outer edge portion of one of said plate pairs is brought to abutment at a second contact plane (20) to an outer edge portion of another of said plate pairs. The outer edge portions (10) are welded. The application also discloses a plate package produced in this manner.
展开▼